Rational design of ROS-responsive nanocarriers for targeted X-ray-induced photodynamic therapy and cascaded chemotherapy of intracranial glioblastoma.

Glioblastoma (GBM) is the most lethal primary intracranial tumor because of its high invasiveness and recurrence. Therefore, nanocarriers with blood-brain barrier (BBB) penetration and transcranial-controlled drug release and activation are rather attractive options for glioblastoma treatment. Herein, we designed a multifunctional nanocarrier (T- TK NP VP ) that combined targeted X-ray-induced photodynamic therapy (X-PDT) and cascaded reactive oxygen species (ROS)-boosted chemotherapy. The T- TK NP VP loaded with verteporfin (VP) and paclitaxel (PTX) was self-assembled from an angiopep-2 (Ang) peptide, functionalized Ang-PEG-DSPE and ROS-sensitive PEG-TK-PTX conjugate. After systemic injection, the T- TK NP VP efficiently crossed the BBB and targeted the GBM cells via receptor-mediated transcytosis. Upon X-ray irradiation, they can generate a certain amount of ROS, which not only induces X-PDT but also locoregionally activates PTX release and action by cleaving the TK bridged bonds. As evidenced by 9.4 T MRI and other experiments, such nanocarriers offer significant growth inhibition of GBM in situ and prolong the survival times of U87-MG tumor-bearing mice. Taken together, the designed T- TK NP VP provided an alternative avenue for realizing transcranial X-PDT and X-ray-activated chemotherapy for targeted and locoregional GBM treatment in vivo .